G
G. Zhang
Researcher at Ames Research Center
Publications - 17
Citations - 1398
G. Zhang is an academic researcher from Ames Research Center. The author has contributed to research in topics: Leaf area index & Tree (data structure). The author has an hindex of 9, co-authored 17 publications receiving 1219 citations. Previous affiliations of G. Zhang include Utah State University.
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Journal ArticleDOI
Intercomparison, interpretation, and assessment of spring phenology in North America estimated from remote sensing for 1982-2006
Michael A. White,Kirsten M. de Beurs,Kamel Didan,David W. Inouye,Andrew D. Richardson,Olaf P. Jensen,John O'Keefe,G. Zhang,Ramakrishna R. Nemani,Willem J. D. van Leeuwen,Jesslyn F. Brown,Allard de Wit,Michael E. Schaepman,Xioamao Lin,Michael D. Dettinger,Amey S. Bailey,John S. Kimball,Mark D. Schwartz,Dennis D. Baldocchi,J. T. Lee,William K. Lauenroth +20 more
TL;DR: In this paper, the authors assess 10 start-of-spring (SOS) methods for North America between 1982 and 2006 and find that SOS estimates were more related to the first leaf and first flowers expanding phenological stages.
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Deriving and validating Leaf Area Index (LAI) at multiple spatial scales through lidar remote sensing: a case study in Sierra National Forest, CA
Hao Tang,Matthew Brolly,Feng Zhao,Feng Zhao,Alan H. Strahler,Crystal L. Schaaf,Crystal L. Schaaf,Sanmay Ganguly,G. Zhang,Ralph Dubayah +9 more
TL;DR: In this paper, an intercomparative study of ground-based, airborne and spaceborne retrievals of total LAI over the conifer-dominated forests of Sierra Nevada in California is presented.
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Generating global Leaf Area Index from Landsat: Algorithm formulation and demonstration
Sanmay Ganguly,Ramakrishna R. Nemani,G. Zhang,Hirofumi Hashimoto,Cristina Milesi,Andrew Michaelis,Weile Wang,Petr Votava,Arindam Samanta,Forrest Melton,Jennifer L. Dungan,Eric Vermote,Feng Gao,Yuri Knyazikhin,Ranga B. Myneni +14 more
TL;DR: In this article, a physically based algorithm for the retrieval of vegetation green leaf area index (LAI) from Landsat surface reflectance data is presented. But the algorithm is based on the canopy spectral invariants theory and provides a computationally efficient way of parameterizing the Bidirectional Reflectance Factor (BRF) as a function of spatial resolution and wavelength.
Journal ArticleDOI
Estimation of forest aboveground biomass in California using canopy height and leaf area index estimated from satellite data
G. Zhang,Sanmay Ganguly,Ramakrishna R. Nemani,Michael A. White,Cristina Milesi,Hirofumi Hashimoto,Weile Wang,Sassan Saatchi,Y. Yu,Ranga B. Myneni +9 more
TL;DR: In this paper, a parametric model that combines high-resolution estimates of leaf area index (LAI) from the Landsat Thematic Mapper sensor and canopy maximum height from the Geoscience Laser Altimeter System (GLAS) sensor onboard ICESat, the Ice, Cloud, and land Elevation Satellite is presented.
Journal ArticleDOI
Large-scale retrieval of leaf area index and vertical foliage profile from the spaceborne waveform lidar (GLAS/ICESat)
TL;DR: In this article, a physically based method of retrieving LAI and vertical foliage profiles (VFPs) from GLAS observations over the entire state of California, USA was developed.